Rotary device for elements subjected to axial movement, particularly for valves in internal combustion engines

ABSTRACT

Valve rotators for spring loaded engine poppet valves or the like operate during decreasing spring loads on the valve closing cycle to effect valve rotation when the valve head is on or closely adjacent the valve seat. The rotator has a valve spring loaded cover, a valve cap with circumferential inclined grooves each receiving a spring urged rolling member and an axially deflectable energy accumulating spring means between the cap and cover engaged by the rolling members. During the valve opening cycle, the spring means is loaded by the cover, and the rolling members are moved to the shallow ends of the inclined grooves unloading the springs acting thereagainst. During the valve closing cycle, the valve spring load on the cover is decreased and the loaded energy accumulating spring means is released, forcing the rolling elements into the deeper ends of the grooves and effecting rotation between the valve cap and cover to rotate the valve.

United States Patent [191 May [4 1 Jan. 16, 1973 [75] Inventor:

many

[73] Assignee: Teves-Thompson Gmbll, Barsinghausen/Hannover, Germany 22 Filed: Nov. 5, 1970 211 App]. No.: 87,300

[30] p 7 Foreign Application Priority Data Kidd ..123/90.3

Arnold May, Bad Nenndorf, Ger- FOREIGN PATENTS OR APPLICATIONS 1,293,789 4/1969 Germany 715,889 9/1954 Great Britain Primary Examiner-Laurence M. Goodridge- Assistant Examiner-Cort Flint Attorney-Hill, Sherman, Meroni, Gross & Simpson 57 ABSTRACT Valve rotators for spring loaded engine poppet valves or the like operate during decreasing spring loads on the valve closing'cycle to effect valve rotation when the valve head is on or closely adjacent the valve seat. The rotator has a valve spring loaded cover, a valve cap with circumferential inclined grooves each receiving a spring urged rolling member and an axially deflectable energy accumulating spring means between the cap and cover engaged by the rolling members. During the valve opening cycle, the spring means is loaded by the cover, and'the rolling members are moved to the shallow ends of the inclined grooves unloading the springs acting thereagainst. During the valve closing cycle, the valve spring load on the cover is decreased and the loaded energy accumulating spring means is released, forcing the rolling elements into the deeper ends of the grooves and effecting rotation between the valve cap and cover to rotate the valve.

10 Claims, 15 Drawing Figures PATENTED JAN 16 I975 SHEET 2 0F 4 INVENTOR:

ATTYS.

PATENTEDJAH 16 I975 SHEET 3 0F 4 INVENTOR: flrno/a May A y'rys.

' RoTARY DEVICE oR ELEMENTS SUBJECTED To AxIAL MOVEMENT, PARTICULARLY FOR vALvEs IN INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to devices for rotating valves or similar elements with axial movement.

2. Prior Art It is old in the art to use devices for rotating valves of internal combustion engines such as gasoline and diesel engines. Such devices normally utilize the increasedvalve spring load which acts axially during lifting of the valve to produce the rotation. With such devices, the valve rotates for a given circumferential degree during the lifting period, but no rotation is provided during the closing period in order to avoid wear at the valve seat. In diesel engines, running with low-grade fuel, however, it is advantageous to rotate the valves during the closing period when they are touching the valve seats in order to remove glazing deposits. This is not possible with valve rotaters constructed according to the prior art, which are operated by the valve spring load.

SUMMARY OF THE INVENTION It is therefore a principle object of this invention to provide a valve rotating device which restricts, by its special design, the formation of deposits on valves, especially with diesel engines running with low-grade fuels.

The solution is accomplished by means effecting rotation during the closing period of the valves, by the valve spring load.

For this purpose, a spring element which is deformable in its axial direction is flattened by the valve spring force during its lifting period. In this manner, rolling or sliding elements, running in grooves of the retainer cap, are caused to roll into the shallow ends of the grooves by the influence of tangentially arranged springs. Thereafter, during the closing period of the valve spring, the spring element releases, activating a force on the rolling or sliding elements, moving those elements to the deeper ends of the grooves. Thereby the spring element moves in relation to the rolling or sliding planes. The inclined races are arranged circumferentially and concentric to an axis so that the movement of the spring element leads to a rotation around the axis.

The devices of this invention can be positioned between the valve spring and the engine body to rotate the valve spring which in turn rotates the valve, or can be positioned between the valvespring and the valve stem where it will directly rotate the valve. In the first embodiment, the valve spring is compressed between a cover of the device and a separate retainer cap locked to the valve stem. In the second embodiment, the valve spring is compressed between the engine body and the cover of the device which has its retainer cap locked to the valve stem. The spring means of the device is loaded when the valve spring load on the cover of the device increases during the valve opening cycle, thereby relieving load on the rolling or sliding elements so thatthe tangential springs may urge these elements into the shallow ends of the grooves in the retainer cap. Thenduring the valve closing cycle, the valve spring load on the cover of the device is relieved, the spring means of the device exerts an axial load on the rolling I or sliding elements causing them to move into the deeper ends of the grooves, and this movement rotates either the cover or the retainer cap to effect rotation of the valve during the valve closing cycle.

I The inclination of the grooves must be of sufficient degree so that all the forces preventingrotation can be BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the invention will be readily apparent from the following description of certain preferred embodiments thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel conceptsof the disclosure, and in which:

FIG. 1 illustrates a preferred embodiment of the valve rotator when subjected to an upward force with FIG. 1a being a fragmentary cross-sectional view of the rotator taken along the indicated line of FIG. lb, which is a fragmentary plan cross-sectional view of the rotator, and FIG. 1c is a fragmentary cross-sectional view taken along the line A-B of FIG. la;

FIG. 2 illustrates the device of FIG. 1 when subjected to circumferential rotation from the position of FIG. 1;

FIG. 2a being a view similar to FIG. 1a, illustrating the rotated elements of the rotator in angular displaced position from FIG. 1;

FIG. 2b is a view similar to'FIG. lb, illustrating the rotational movement;

FIG. 20 is a view similar to FIG. 1c,-illustrating the movement of the roller element in the inclined groove;

FIGS. 1 and 2 in views-similar to 2a and 2c;

FIG. 4 illustrates yet another embodiment of the rotator of this invention;

FIGS is a view similar to FIG. 4 and FIG. la, illustrating yet another embodiment of this invention;

FIG. 6 is a view similar to FIG. 1a, illustrating a modified form of this invention with a ball race interposed between rolling elements and-the spring element;

FIG. 7 is a view similar to FIG. la illustrating yet another modified form of this invention;

FIG. 8 is a view similar to FIG. la illustrating a spring-urged modified form of this invention;

FIG. 9 is a view similar to FIG. 8, illustrating the use of a raceway in the spring-urged disk.

. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the rotatorwith the valve in fullyopened position withspring element 1 under tension,

tion before rotation starts. The grooves 4, inclined under angle 41 machined in the retainer cap 3, are

the base plate which is fixed to the retainer cap 3 and.

ponents of forces in peripheral direction, roll in' grooves 4 and transfer their rolling action onto spring element 1, which makes twice the travel of balls 2 and rotates around axis a-b of retainer cap 3. Using sliding elements instead of rolling elements, spring element 1 will just have the same travel as the sliding elements.

FIG. 2 shows the position when rotation has ended.

I Balls 2 are situated in the maximal attainable depth of grooves 4. They have been rolled from position 1 in FIG. lb to position 2 in FIG. 2b, thereby making rotation covering the angle L, on the rolling radius r oras shown in FIG. 20 a rolling distance r so that spring element 1 theoretically has been rotated for 2; and covered the rolling distance 2r.

If no axial force acts any longer on the cover 6, this cover is supported by the safety ring 8, and balls 2 come in contact with grooves 4 and with spring element 1 in proportion to the tangential spring forces. This position is also obtainable if cover 6 is still axially loaded so that spring element 1 has to exert a corresponding counterforce action.

FIG. 3 shows a version of rotator installed at tip-end of valve. Bore of retainer cap 3 is a taper 24 to fit the retainer locks. Retainer cap 3 rotates against spring element 1 which is in contact with cover 9. Said cover 9 forms the support for valve spring 10 and is fixed against rotation by said valve spring 10.

FIG. 4 shows a device similar to FIG. 1 and FIG. 2 wherebya beaded flange 25 of cover 11 around a shoulder 26 of part 13 replaces safety or retainer ring 8.

FIG. 5 shows a version which combines elements of FIG. 3 and FIG. 4. The beaded cover 12 acts also as a support for valve spring 10. Base plate 5, FIG. 1 and FIG. 2, is replaced by the flange of part 13 having taper 24 to fit the retainer locks.

FIG. 6 shows a ball race 14 between rolling elements 2'and spring element 1, said ball race 14 reducing the contact pressure at spring element 1 as said spring element 1 now supports on a bulge 27 with linear contact.

FIG. 7 shows a design especially suitable if a high torque of the rotator is required. Two spring washers 15a and 15b act as one spring element, said spring washers loading the base plate 5 indirect over anti-friction bearing 16. The loads for the spring washers 15a and 15b are applied by one or a plurality of valve springs 10 and 18 and cover 19 acting as a spring sup port. The friction between baseplate 5 and spring element 1 being reduced by the antifriction bearing 16 makes it sometimes necessary'to install an additional brake disk 20 between spring element 1 and retainer cap 3, to prevent uncontrolled rotation of the spring element 1 against retainer cap 3 in the loadingperiod.

FIG. 8 shows said spring element 1 consisting of a disk 21 into which a raceway 22 might be machined see FIG. 9 Said disk 21 supported by an antifriction bearing 16 and coil springs 23 orv any other elastical members. The overall height of part 13 is so dimeng [claim as myinvention:

sioned as to limit the axial movement of disk 21 to a predetermined size.

Although the teachings of my invention have herein been discussed with reference to specific theories and embodiments, it is to be understood that these are by way of illustration only and that others may wish to utilize my invention in different designs or applications.

1. A rotator adapted for rotating spring loaded en gine poppet valves during the valve closing cycle which comprises a cap having circumferential grooves with inclined bottoms, rolling elements received in said grooves, springs urging the rolling elements toward the shallow ends of the grooves, a base plateon the cap, a cover adapted to be loaded by the valve spring, a spring means between the base plate of the cap and the cover loaded in the direction of the valve axis during the valve opening cycle, said rolling elements engageable with said spring means and urged by the springs acting thereagainst into the shallow ends of the grooves when the spring means is loaded during the valve opening cycle and said rolling elements being subject to increased load when the load on the spring means is decreased during the valve closing cycle thereby effecting relative rotation between the cap and the cover.

2. The rotator of claim 1 wherein the the base plate is fixed to the cap, thespring means rests on the base plate, the spring means rotates relative to the cap and the cover is rotated by the spring means to rotate the valve spring and valve.

3. The rotator of claim. 1 wherein the spring means rotates the cap and the cap is locked on the valve stem to transfer rotation to thevalve stem.

4. The rotator of claim 2 including anti-friction means between the spring means and the base plate.

5. The rotator of claim 1 including a flange on a I sleeveconnected to the retainer cap.

6. The rotator of claim 1 wherein the spring-means is a Belleville washer. i 7. The rotator of claim 1 wherein the spring means is a flat disc having a plurality of coil springs acting.

thereagainst.

8. The rotator of claim 7 wherein an anti-friction bearing is provided between the coil springs and the base plate.

9. The rotator of claim 1 wherein a conical washer is placed between the spring means and the retainer cap.

10. A rotator for rotating a spring loaded engine poppet valve during the valve closing cycle which comprises a first part to be loaded by the valve spring, a second part axially shiftable relative to the firstpart, an energy accumulator spring means urging the first and second parts into axially extended relationship and biased duringthe valve opening cycle, said second part having axially inclined circumferential grooves, rolling elements seated in said grooves, spring means urging I the rolling elements into the shallow ends of the grooves during the valve opening cycle, and said rolling elements being driven cireumferentially by release of energy from the energy accumulator spring means during the valve closing cycle to effect relative rotation of the first and second partsr 

1. A rotator adapted for rotating spring loaded engine poppet valves during the valve closing cycle which comprises a cap having circumferential grooves with inclined bottoms, rolling elements received in said grooves, springs urging the rolling elements toward the shallow ends of the grooves, a base plate on the cap, a cover adapted to be loaded by the valve spring, a spring means between the base plate of the cap and the cover loaded in the direction of the valve axis during the valve opening cycle, said rolling elements engageable with said spring means and urged by the springs acting thereagainst into the shallow ends of the grooves when the spring means is loaded during the valve opening cycle and said rolling elements being subject to increased load when the load on the spring means is decreased during the valve closing cycle thereby effecting relative rotation between the cap and the cover.
 2. The rotator of claim 1 wherein the the base plate is fixed to the cap, the spring means rests on the base plate, the spring means rotates relative to the cap and the cover is rotated by the spring means to rotate the valve spring and valve.
 3. The rotator of claim 1 wherein the spring means rotates the cap and the cap is locked on the valve stem to transfer rotation to the valve stem.
 4. The rotator of claim 2 including anti-friction means between the spring means and the base plate.
 5. The rotator of claim 1 including a flange on a sleeve connected to the retainer cap.
 6. The rotator of claim 1 wherein the spring means is a Belleville washer.
 7. The rotator of claim 1 wherein the spring means is a flat disc having a plurality of coil springs acting thereagainst.
 8. The rotator of claim 7 wherein an anti-friction bearing is provided between the coil springs and the base plate.
 9. The rotator of claim 1 wherein a conical washer is placed between the spring means and the retainer cap.
 10. A rotator for rotating a spring loaded engine poppet valve during the valve closing cycle which comprises a first part to be loaded by the valve spring, a second part axially shiftable relative to the first part, an energy accumulator spring means urging the first and second parts into axially extended relationship and biased during the valve opening cycle, said second part having axially inclined circumferential grooves, rolling elements seated in said grooves, spring means urging the rolling elements into the shallow ends of the grooves during the valve opening cycle, and said rolling elements being driven circumferentially by release of energy from the energy accumulator spring means during the valve closing cycle to effect relative rotation of the first and second parts. 